This paper reviews work done since January 1972 in children's language acquisition and development. It is divided into the following sections: (1) a brief summary of descriptive studies of adult and child speech, (2) a review of the results of three types of manipulative studies, and (3) a discussion of J. Gruber's interpretation of early acquisition data. A discussion of apparent problems and trends in the current approaches to language acquisition study and an extensive bibliography conclude the paper. (Author/PMP)